In the end, the no-framework framework that Rasmus proposes isn’t so much of a framework as a coding style / approach, and he basically advocates rolling your own instead of refactoring someone else’s complicated framework. Still, some good points and worth checking out, good comments at the bottom too…

Try to avoid using include_once and require_once if possible. You are much better off using a straight include or require call, because the *_once() calls are very slow under an opcode cache. Sometimes there is no way around using these calls, but recognize that each one costs you an extra open() syscall and hash look up.
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Nothing is going to build your application for you, no matter what it promises. You are going to have to build it yourself. Instead of starting by fixing the mistakes in some foreign framework and refactoring all the things that don’t apply to your environment spend your time building a lean and reusable pattern that fits your requirements directly. In the end I think you will find that your homegrown small framework has saved you time and aggravation and you end up with a better product.